Synthesis and thermoluminescence properties of MgAl2O4:Ca laser-sintered ceramics

Abstract Ceramic materials are low cost and have a good thermal and mechanic resistance which are suitable characteristics for a good dosimeter. A new Ca-doped MgAl2O4 ceramic material was produced by the first time by the laser sintering method. Thermoluminescence (TL) properties as a function of the exposure to ionizing radiation were investigated. X-ray diffraction of the sintered samples showed single crystalline phase corresponding to the cubic spinel structure. SEM images reveal the microstructure with homogenous and faceted grains and low porosity. TL readouts were performed with a linear heating rate were performed after irradiation with beta particles (doses ranging from 0.02 to 5 Gy). The TL glow-curve shows a single and wide peak centered at about 170 °C with a linear dose response, good repeatability (~ 1%) and immediate fading that stabilizes after ~ 16 h with 80% of the initial intensity. The lowest detectable dose (LDD) was also evaluated at ~ 20 μGy. By applying the Tm-Tstop method to analyze the glow curve, it was found a behavior characteristic of closely overlapping or a quasi-continuum of peaks. Initial rise, peak shape of the TL glow curve, the TL glow curve area, and glow curve fitting methods were used to obtain the kinetic parameters of the glow peak. In general, the TL results suggest that this material might be used in dosimetric applications considering the studied dose range.